Child advocates are urging Facebook to abort Messenger Kids, a messaging app designed for children younger than the 13-year-old minimum age the company requires for its other social products. 

"Younger children are simply not ready to have social media accounts,"  Campaign for a Commercial-Free Childhood, a Boston-based nonprofit advocacy group, said Tuesday in a letter.

The letter was signed by 19 other organizations and dozens of individual child experts and addressed to Facebook CEO Mark Zuckerberg. 

A Messenger spokesman said the app helps parents and children chat in a safe way and gives parents control of their kids' contacts and interactions. 

"We worked to create Messenger Kids with an advisory committee of parenting and developmental experts, as well as with families themselves and in partnership with the PTA," the spokesman said in a statement, referencing the National Parent Teacher Association. "We continue to be focused on making Messenger Kids be the best experience it can be for families. We have been very clear that there is no advertising in Messenger Kids."

However, the Campaign for a Commercial-Free Childhood said that children under 13 are too young to grapple with the complexities of online relationships and will use the app lacking a comprehensive understanding of privacy, such as what's appropriate to share and who has access to their conversations, pictures and videos.

Apps aimed at children have come under renewed scrutiny for exposing some of the perils of tech giants' massive scale. Companies like Facebook, with more than 2 billion monthly users, and Google's YouTube Kids app have been criticized for pitching products as safe for children but then being unable to keep up when a flood of content lets inappropriate items slip through. 

The Campaign for a Commercial-Free Childhood has previously criticized other kid-focused tech. In 2013, it complained about claims made by Fisher-Price and Disney's "Baby Einstein" brand that mobile apps could be educational for babies. In 2015, it accused Google's YouTube Kids app of letting inappropriate material slip through the cracks of what was touted to be a child-safe video zone. Last year, it joined a coalition of advocacy groups protesting an artificial-intelligence-powered home hub aimed at kids by Mattel. 

On Tuesday, the group called Facebook "especially irresponsible" for encouraging children as young as preschool age to begin a social-media habit. While Facebook has explained the app is a way to talk to family and friends over long distances, the advocacy group noted such communication doesn't require a Messenger Kids account. 

Kids can use parents' accounts on Facebook, Skype or other services to chat with relatives, the group noted. "They can also just pick up a phone," the group wrote.

"Raising children in our new digital age is difficult enough," it added. "We ask that you do not use Facebook's enormous reach and influence to make it even harder."

Originally published Jan. 30 at 7:11 a.m. PT.
Update, 8:09 a.m. PT: Comment from Facebook Messenger added. 

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